1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * bcm2835 sdhost driver.
4 *
5 * The 2835 has two SD controllers: The Arasan sdhci controller
6 * (supported by the iproc driver) and a custom sdhost controller
7 * (supported by this driver).
8 *
9 * The sdhci controller supports both sdcard and sdio. The sdhost
10 * controller supports the sdcard only, but has better performance.
11 * Also note that the rpi3 has sdio wifi, so driving the sdcard with
12 * the sdhost controller allows to use the sdhci controller for wifi
13 * support.
14 *
15 * The configuration is done by devicetree via pin muxing. Both
16 * SD controller are available on the same pins (2 pin groups = pin 22
17 * to 27 + pin 48 to 53). So it's possible to use both SD controllers
18 * at the same time with different pin groups.
19 *
20 * Author: Phil Elwell <phil@raspberrypi.org>
21 * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
22 *
23 * Based on
24 * mmc-bcm2835.c by Gellert Weisz
25 * which is, in turn, based on
26 * sdhci-bcm2708.c by Broadcom
27 * sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko
28 * sdhci.c and sdhci-pci.c by Pierre Ossman
29 */
30 #include <linux/clk.h>
31 #include <linux/delay.h>
32 #include <linux/device.h>
33 #include <linux/dmaengine.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/err.h>
36 #include <linux/highmem.h>
37 #include <linux/interrupt.h>
38 #include <linux/io.h>
39 #include <linux/iopoll.h>
40 #include <linux/module.h>
41 #include <linux/of_address.h>
42 #include <linux/of_irq.h>
43 #include <linux/platform_device.h>
44 #include <linux/scatterlist.h>
45 #include <linux/time.h>
46 #include <linux/workqueue.h>
47
48 #include <linux/mmc/host.h>
49 #include <linux/mmc/mmc.h>
50 #include <linux/mmc/sd.h>
51
52 #define SDCMD 0x00 /* Command to SD card - 16 R/W */
53 #define SDARG 0x04 /* Argument to SD card - 32 R/W */
54 #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
55 #define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */
56 #define SDRSP0 0x10 /* SD card response (31:0) - 32 R */
57 #define SDRSP1 0x14 /* SD card response (63:32) - 32 R */
58 #define SDRSP2 0x18 /* SD card response (95:64) - 32 R */
59 #define SDRSP3 0x1c /* SD card response (127:96) - 32 R */
60 #define SDHSTS 0x20 /* SD host status - 11 R/W */
61 #define SDVDD 0x30 /* SD card power control - 1 R/W */
62 #define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */
63 #define SDHCFG 0x38 /* Host configuration - 2 R/W */
64 #define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */
65 #define SDDATA 0x40 /* Data to/from SD card - 32 R/W */
66 #define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */
67
68 #define SDCMD_NEW_FLAG 0x8000
69 #define SDCMD_FAIL_FLAG 0x4000
70 #define SDCMD_BUSYWAIT 0x800
71 #define SDCMD_NO_RESPONSE 0x400
72 #define SDCMD_LONG_RESPONSE 0x200
73 #define SDCMD_WRITE_CMD 0x80
74 #define SDCMD_READ_CMD 0x40
75 #define SDCMD_CMD_MASK 0x3f
76
77 #define SDCDIV_MAX_CDIV 0x7ff
78
79 #define SDHSTS_BUSY_IRPT 0x400
80 #define SDHSTS_BLOCK_IRPT 0x200
81 #define SDHSTS_SDIO_IRPT 0x100
82 #define SDHSTS_REW_TIME_OUT 0x80
83 #define SDHSTS_CMD_TIME_OUT 0x40
84 #define SDHSTS_CRC16_ERROR 0x20
85 #define SDHSTS_CRC7_ERROR 0x10
86 #define SDHSTS_FIFO_ERROR 0x08
87 /* Reserved */
88 /* Reserved */
89 #define SDHSTS_DATA_FLAG 0x01
90
91 #define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \
92 SDHSTS_CRC16_ERROR | \
93 SDHSTS_REW_TIME_OUT | \
94 SDHSTS_FIFO_ERROR)
95
96 #define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \
97 SDHSTS_TRANSFER_ERROR_MASK)
98
99 #define SDHCFG_BUSY_IRPT_EN BIT(10)
100 #define SDHCFG_BLOCK_IRPT_EN BIT(8)
101 #define SDHCFG_SDIO_IRPT_EN BIT(5)
102 #define SDHCFG_DATA_IRPT_EN BIT(4)
103 #define SDHCFG_SLOW_CARD BIT(3)
104 #define SDHCFG_WIDE_EXT_BUS BIT(2)
105 #define SDHCFG_WIDE_INT_BUS BIT(1)
106 #define SDHCFG_REL_CMD_LINE BIT(0)
107
108 #define SDVDD_POWER_OFF 0
109 #define SDVDD_POWER_ON 1
110
111 #define SDEDM_FORCE_DATA_MODE BIT(19)
112 #define SDEDM_CLOCK_PULSE BIT(20)
113 #define SDEDM_BYPASS BIT(21)
114
115 #define SDEDM_WRITE_THRESHOLD_SHIFT 9
116 #define SDEDM_READ_THRESHOLD_SHIFT 14
117 #define SDEDM_THRESHOLD_MASK 0x1f
118
119 #define SDEDM_FSM_MASK 0xf
120 #define SDEDM_FSM_IDENTMODE 0x0
121 #define SDEDM_FSM_DATAMODE 0x1
122 #define SDEDM_FSM_READDATA 0x2
123 #define SDEDM_FSM_WRITEDATA 0x3
124 #define SDEDM_FSM_READWAIT 0x4
125 #define SDEDM_FSM_READCRC 0x5
126 #define SDEDM_FSM_WRITECRC 0x6
127 #define SDEDM_FSM_WRITEWAIT1 0x7
128 #define SDEDM_FSM_POWERDOWN 0x8
129 #define SDEDM_FSM_POWERUP 0x9
130 #define SDEDM_FSM_WRITESTART1 0xa
131 #define SDEDM_FSM_WRITESTART2 0xb
132 #define SDEDM_FSM_GENPULSES 0xc
133 #define SDEDM_FSM_WRITEWAIT2 0xd
134 #define SDEDM_FSM_STARTPOWDOWN 0xf
135
136 #define SDDATA_FIFO_WORDS 16
137
138 #define FIFO_READ_THRESHOLD 4
139 #define FIFO_WRITE_THRESHOLD 4
140 #define SDDATA_FIFO_PIO_BURST 8
141
142 #define PIO_THRESHOLD 1 /* Maximum block count for PIO (0 = always DMA) */
143
144 struct bcm2835_host {
145 spinlock_t lock;
146 struct mutex mutex;
147
148 void __iomem *ioaddr;
149 u32 phys_addr;
150
151 struct platform_device *pdev;
152
153 int clock; /* Current clock speed */
154 unsigned int max_clk; /* Max possible freq */
155 struct work_struct dma_work;
156 struct delayed_work timeout_work; /* Timer for timeouts */
157 struct sg_mapping_iter sg_miter; /* SG state for PIO */
158 unsigned int blocks; /* remaining PIO blocks */
159 int irq; /* Device IRQ */
160
161 u32 ns_per_fifo_word;
162
163 /* cached registers */
164 u32 hcfg;
165 u32 cdiv;
166
167 struct mmc_request *mrq; /* Current request */
168 struct mmc_command *cmd; /* Current command */
169 struct mmc_data *data; /* Current data request */
170 bool data_complete:1;/* Data finished before cmd */
171 bool use_busy:1; /* Wait for busy interrupt */
172 bool use_sbc:1; /* Send CMD23 */
173
174 /* for threaded irq handler */
175 bool irq_block;
176 bool irq_busy;
177 bool irq_data;
178
179 /* DMA part */
180 struct dma_chan *dma_chan_rxtx;
181 struct dma_chan *dma_chan;
182 struct dma_slave_config dma_cfg_rx;
183 struct dma_slave_config dma_cfg_tx;
184 struct dma_async_tx_descriptor *dma_desc;
185 u32 dma_dir;
186 u32 drain_words;
187 struct page *drain_page;
188 u32 drain_offset;
189 bool use_dma;
190 };
191
bcm2835_dumpcmd(struct bcm2835_host * host,struct mmc_command * cmd,const char * label)192 static void bcm2835_dumpcmd(struct bcm2835_host *host, struct mmc_command *cmd,
193 const char *label)
194 {
195 struct device *dev = &host->pdev->dev;
196
197 if (!cmd)
198 return;
199
200 dev_dbg(dev, "%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n",
201 (cmd == host->cmd) ? '>' : ' ',
202 label, cmd->opcode, cmd->arg, cmd->flags,
203 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3],
204 cmd->error);
205 }
206
bcm2835_dumpregs(struct bcm2835_host * host)207 static void bcm2835_dumpregs(struct bcm2835_host *host)
208 {
209 struct mmc_request *mrq = host->mrq;
210 struct device *dev = &host->pdev->dev;
211
212 if (mrq) {
213 bcm2835_dumpcmd(host, mrq->sbc, "sbc");
214 bcm2835_dumpcmd(host, mrq->cmd, "cmd");
215 if (mrq->data) {
216 dev_dbg(dev, "data blocks %x blksz %x - err %d\n",
217 mrq->data->blocks,
218 mrq->data->blksz,
219 mrq->data->error);
220 }
221 bcm2835_dumpcmd(host, mrq->stop, "stop");
222 }
223
224 dev_dbg(dev, "=========== REGISTER DUMP ===========\n");
225 dev_dbg(dev, "SDCMD 0x%08x\n", readl(host->ioaddr + SDCMD));
226 dev_dbg(dev, "SDARG 0x%08x\n", readl(host->ioaddr + SDARG));
227 dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT));
228 dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV));
229 dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0));
230 dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1));
231 dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2));
232 dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3));
233 dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS));
234 dev_dbg(dev, "SDVDD 0x%08x\n", readl(host->ioaddr + SDVDD));
235 dev_dbg(dev, "SDEDM 0x%08x\n", readl(host->ioaddr + SDEDM));
236 dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG));
237 dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT));
238 dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC));
239 dev_dbg(dev, "===========================================\n");
240 }
241
bcm2835_reset_internal(struct bcm2835_host * host)242 static void bcm2835_reset_internal(struct bcm2835_host *host)
243 {
244 u32 temp;
245
246 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
247 writel(0, host->ioaddr + SDCMD);
248 writel(0, host->ioaddr + SDARG);
249 writel(0xf00000, host->ioaddr + SDTOUT);
250 writel(0, host->ioaddr + SDCDIV);
251 writel(0x7f8, host->ioaddr + SDHSTS); /* Write 1s to clear */
252 writel(0, host->ioaddr + SDHCFG);
253 writel(0, host->ioaddr + SDHBCT);
254 writel(0, host->ioaddr + SDHBLC);
255
256 /* Limit fifo usage due to silicon bug */
257 temp = readl(host->ioaddr + SDEDM);
258 temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |
259 (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));
260 temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
261 (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
262 writel(temp, host->ioaddr + SDEDM);
263 msleep(20);
264 writel(SDVDD_POWER_ON, host->ioaddr + SDVDD);
265 msleep(20);
266 host->clock = 0;
267 writel(host->hcfg, host->ioaddr + SDHCFG);
268 writel(host->cdiv, host->ioaddr + SDCDIV);
269 }
270
bcm2835_reset(struct mmc_host * mmc)271 static void bcm2835_reset(struct mmc_host *mmc)
272 {
273 struct bcm2835_host *host = mmc_priv(mmc);
274
275 if (host->dma_chan)
276 dmaengine_terminate_sync(host->dma_chan);
277 host->dma_chan = NULL;
278 bcm2835_reset_internal(host);
279 }
280
281 static void bcm2835_finish_command(struct bcm2835_host *host);
282
bcm2835_wait_transfer_complete(struct bcm2835_host * host)283 static void bcm2835_wait_transfer_complete(struct bcm2835_host *host)
284 {
285 int timediff;
286 u32 alternate_idle;
287
288 alternate_idle = (host->mrq->data->flags & MMC_DATA_READ) ?
289 SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1;
290
291 timediff = 0;
292
293 while (1) {
294 u32 edm, fsm;
295
296 edm = readl(host->ioaddr + SDEDM);
297 fsm = edm & SDEDM_FSM_MASK;
298
299 if ((fsm == SDEDM_FSM_IDENTMODE) ||
300 (fsm == SDEDM_FSM_DATAMODE))
301 break;
302 if (fsm == alternate_idle) {
303 writel(edm | SDEDM_FORCE_DATA_MODE,
304 host->ioaddr + SDEDM);
305 break;
306 }
307
308 timediff++;
309 if (timediff == 100000) {
310 dev_err(&host->pdev->dev,
311 "wait_transfer_complete - still waiting after %d retries\n",
312 timediff);
313 bcm2835_dumpregs(host);
314 host->mrq->data->error = -ETIMEDOUT;
315 return;
316 }
317 cpu_relax();
318 }
319 }
320
bcm2835_dma_complete(void * param)321 static void bcm2835_dma_complete(void *param)
322 {
323 struct bcm2835_host *host = param;
324
325 schedule_work(&host->dma_work);
326 }
327
bcm2835_transfer_block_pio(struct bcm2835_host * host,bool is_read)328 static void bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read)
329 {
330 unsigned long flags;
331 size_t blksize;
332 unsigned long wait_max;
333
334 blksize = host->data->blksz;
335
336 wait_max = jiffies + msecs_to_jiffies(500);
337
338 local_irq_save(flags);
339
340 while (blksize) {
341 int copy_words;
342 u32 hsts = 0;
343 size_t len;
344 u32 *buf;
345
346 if (!sg_miter_next(&host->sg_miter)) {
347 host->data->error = -EINVAL;
348 break;
349 }
350
351 len = min(host->sg_miter.length, blksize);
352 if (len % 4) {
353 host->data->error = -EINVAL;
354 break;
355 }
356
357 blksize -= len;
358 host->sg_miter.consumed = len;
359
360 buf = (u32 *)host->sg_miter.addr;
361
362 copy_words = len / 4;
363
364 while (copy_words) {
365 int burst_words, words;
366 u32 edm;
367
368 burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words);
369 edm = readl(host->ioaddr + SDEDM);
370 if (is_read)
371 words = ((edm >> 4) & 0x1f);
372 else
373 words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f);
374
375 if (words < burst_words) {
376 int fsm_state = (edm & SDEDM_FSM_MASK);
377 struct device *dev = &host->pdev->dev;
378
379 if ((is_read &&
380 (fsm_state != SDEDM_FSM_READDATA &&
381 fsm_state != SDEDM_FSM_READWAIT &&
382 fsm_state != SDEDM_FSM_READCRC)) ||
383 (!is_read &&
384 (fsm_state != SDEDM_FSM_WRITEDATA &&
385 fsm_state != SDEDM_FSM_WRITESTART1 &&
386 fsm_state != SDEDM_FSM_WRITESTART2))) {
387 hsts = readl(host->ioaddr + SDHSTS);
388 dev_err(dev, "fsm %x, hsts %08x\n",
389 fsm_state, hsts);
390 if (hsts & SDHSTS_ERROR_MASK)
391 break;
392 }
393
394 if (time_after(jiffies, wait_max)) {
395 dev_err(dev, "PIO %s timeout - EDM %08x\n",
396 is_read ? "read" : "write",
397 edm);
398 hsts = SDHSTS_REW_TIME_OUT;
399 break;
400 }
401 ndelay((burst_words - words) *
402 host->ns_per_fifo_word);
403 continue;
404 } else if (words > copy_words) {
405 words = copy_words;
406 }
407
408 copy_words -= words;
409
410 while (words) {
411 if (is_read)
412 *(buf++) = readl(host->ioaddr + SDDATA);
413 else
414 writel(*(buf++), host->ioaddr + SDDATA);
415 words--;
416 }
417 }
418
419 if (hsts & SDHSTS_ERROR_MASK)
420 break;
421 }
422
423 sg_miter_stop(&host->sg_miter);
424
425 local_irq_restore(flags);
426 }
427
bcm2835_transfer_pio(struct bcm2835_host * host)428 static void bcm2835_transfer_pio(struct bcm2835_host *host)
429 {
430 struct device *dev = &host->pdev->dev;
431 u32 sdhsts;
432 bool is_read;
433
434 is_read = (host->data->flags & MMC_DATA_READ) != 0;
435 bcm2835_transfer_block_pio(host, is_read);
436
437 sdhsts = readl(host->ioaddr + SDHSTS);
438 if (sdhsts & (SDHSTS_CRC16_ERROR |
439 SDHSTS_CRC7_ERROR |
440 SDHSTS_FIFO_ERROR)) {
441 dev_err(dev, "%s transfer error - HSTS %08x\n",
442 is_read ? "read" : "write", sdhsts);
443 host->data->error = -EILSEQ;
444 } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
445 SDHSTS_REW_TIME_OUT))) {
446 dev_err(dev, "%s timeout error - HSTS %08x\n",
447 is_read ? "read" : "write", sdhsts);
448 host->data->error = -ETIMEDOUT;
449 }
450 }
451
452 static
bcm2835_prepare_dma(struct bcm2835_host * host,struct mmc_data * data)453 void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data)
454 {
455 int sg_len, dir_data, dir_slave;
456 struct dma_async_tx_descriptor *desc = NULL;
457 struct dma_chan *dma_chan;
458
459 dma_chan = host->dma_chan_rxtx;
460 if (data->flags & MMC_DATA_READ) {
461 dir_data = DMA_FROM_DEVICE;
462 dir_slave = DMA_DEV_TO_MEM;
463 } else {
464 dir_data = DMA_TO_DEVICE;
465 dir_slave = DMA_MEM_TO_DEV;
466 }
467
468 /* The block doesn't manage the FIFO DREQs properly for
469 * multi-block transfers, so don't attempt to DMA the final
470 * few words. Unfortunately this requires the final sg entry
471 * to be trimmed. N.B. This code demands that the overspill
472 * is contained in a single sg entry.
473 */
474
475 host->drain_words = 0;
476 if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) {
477 struct scatterlist *sg;
478 u32 len;
479 int i;
480
481 len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4,
482 (u32)data->blocks * data->blksz);
483
484 for_each_sg(data->sg, sg, data->sg_len, i) {
485 if (sg_is_last(sg)) {
486 WARN_ON(sg->length < len);
487 sg->length -= len;
488 host->drain_page = sg_page(sg);
489 host->drain_offset = sg->offset + sg->length;
490 }
491 }
492 host->drain_words = len / 4;
493 }
494
495 /* The parameters have already been validated, so this will not fail */
496 (void)dmaengine_slave_config(dma_chan,
497 (dir_data == DMA_FROM_DEVICE) ?
498 &host->dma_cfg_rx :
499 &host->dma_cfg_tx);
500
501 sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,
502 dir_data);
503 if (!sg_len)
504 return;
505
506 desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave,
507 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
508
509 if (!desc) {
510 dma_unmap_sg(dma_chan->device->dev, data->sg, sg_len, dir_data);
511 return;
512 }
513
514 desc->callback = bcm2835_dma_complete;
515 desc->callback_param = host;
516 host->dma_desc = desc;
517 host->dma_chan = dma_chan;
518 host->dma_dir = dir_data;
519 }
520
bcm2835_start_dma(struct bcm2835_host * host)521 static void bcm2835_start_dma(struct bcm2835_host *host)
522 {
523 dmaengine_submit(host->dma_desc);
524 dma_async_issue_pending(host->dma_chan);
525 }
526
bcm2835_set_transfer_irqs(struct bcm2835_host * host)527 static void bcm2835_set_transfer_irqs(struct bcm2835_host *host)
528 {
529 u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN |
530 SDHCFG_BUSY_IRPT_EN;
531
532 if (host->dma_desc) {
533 host->hcfg = (host->hcfg & ~all_irqs) |
534 SDHCFG_BUSY_IRPT_EN;
535 } else {
536 host->hcfg = (host->hcfg & ~all_irqs) |
537 SDHCFG_DATA_IRPT_EN |
538 SDHCFG_BUSY_IRPT_EN;
539 }
540
541 writel(host->hcfg, host->ioaddr + SDHCFG);
542 }
543
544 static
bcm2835_prepare_data(struct bcm2835_host * host,struct mmc_command * cmd)545 void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_command *cmd)
546 {
547 struct mmc_data *data = cmd->data;
548
549 WARN_ON(host->data);
550
551 host->data = data;
552 if (!data)
553 return;
554
555 host->data_complete = false;
556 host->data->bytes_xfered = 0;
557
558 if (!host->dma_desc) {
559 /* Use PIO */
560 int flags = SG_MITER_ATOMIC;
561
562 if (data->flags & MMC_DATA_READ)
563 flags |= SG_MITER_TO_SG;
564 else
565 flags |= SG_MITER_FROM_SG;
566 sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
567 host->blocks = data->blocks;
568 }
569
570 bcm2835_set_transfer_irqs(host);
571
572 writel(data->blksz, host->ioaddr + SDHBCT);
573 writel(data->blocks, host->ioaddr + SDHBLC);
574 }
575
bcm2835_read_wait_sdcmd(struct bcm2835_host * host,u32 max_ms)576 static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms)
577 {
578 struct device *dev = &host->pdev->dev;
579 u32 value;
580 int ret;
581
582 ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
583 !(value & SDCMD_NEW_FLAG), 1, 10);
584 if (ret == -ETIMEDOUT)
585 /* if it takes a while make poll interval bigger */
586 ret = readl_poll_timeout(host->ioaddr + SDCMD, value,
587 !(value & SDCMD_NEW_FLAG),
588 10, max_ms * 1000);
589 if (ret == -ETIMEDOUT)
590 dev_err(dev, "%s: timeout (%d ms)\n", __func__, max_ms);
591
592 return value;
593 }
594
bcm2835_finish_request(struct bcm2835_host * host)595 static void bcm2835_finish_request(struct bcm2835_host *host)
596 {
597 struct dma_chan *terminate_chan = NULL;
598 struct mmc_request *mrq;
599
600 cancel_delayed_work(&host->timeout_work);
601
602 mrq = host->mrq;
603
604 host->mrq = NULL;
605 host->cmd = NULL;
606 host->data = NULL;
607
608 host->dma_desc = NULL;
609 terminate_chan = host->dma_chan;
610 host->dma_chan = NULL;
611
612 if (terminate_chan) {
613 int err = dmaengine_terminate_all(terminate_chan);
614
615 if (err)
616 dev_err(&host->pdev->dev,
617 "failed to terminate DMA (%d)\n", err);
618 }
619
620 mmc_request_done(mmc_from_priv(host), mrq);
621 }
622
623 static
bcm2835_send_command(struct bcm2835_host * host,struct mmc_command * cmd)624 bool bcm2835_send_command(struct bcm2835_host *host, struct mmc_command *cmd)
625 {
626 struct device *dev = &host->pdev->dev;
627 u32 sdcmd, sdhsts;
628 unsigned long timeout;
629
630 WARN_ON(host->cmd);
631
632 sdcmd = bcm2835_read_wait_sdcmd(host, 100);
633 if (sdcmd & SDCMD_NEW_FLAG) {
634 dev_err(dev, "previous command never completed.\n");
635 bcm2835_dumpregs(host);
636 cmd->error = -EILSEQ;
637 bcm2835_finish_request(host);
638 return false;
639 }
640
641 if (!cmd->data && cmd->busy_timeout > 9000)
642 timeout = DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
643 else
644 timeout = 10 * HZ;
645 schedule_delayed_work(&host->timeout_work, timeout);
646
647 host->cmd = cmd;
648
649 /* Clear any error flags */
650 sdhsts = readl(host->ioaddr + SDHSTS);
651 if (sdhsts & SDHSTS_ERROR_MASK)
652 writel(sdhsts, host->ioaddr + SDHSTS);
653
654 if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
655 dev_err(dev, "unsupported response type!\n");
656 cmd->error = -EINVAL;
657 bcm2835_finish_request(host);
658 return false;
659 }
660
661 bcm2835_prepare_data(host, cmd);
662
663 writel(cmd->arg, host->ioaddr + SDARG);
664
665 sdcmd = cmd->opcode & SDCMD_CMD_MASK;
666
667 host->use_busy = false;
668 if (!(cmd->flags & MMC_RSP_PRESENT)) {
669 sdcmd |= SDCMD_NO_RESPONSE;
670 } else {
671 if (cmd->flags & MMC_RSP_136)
672 sdcmd |= SDCMD_LONG_RESPONSE;
673 if (cmd->flags & MMC_RSP_BUSY) {
674 sdcmd |= SDCMD_BUSYWAIT;
675 host->use_busy = true;
676 }
677 }
678
679 if (cmd->data) {
680 if (cmd->data->flags & MMC_DATA_WRITE)
681 sdcmd |= SDCMD_WRITE_CMD;
682 if (cmd->data->flags & MMC_DATA_READ)
683 sdcmd |= SDCMD_READ_CMD;
684 }
685
686 writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD);
687
688 return true;
689 }
690
bcm2835_transfer_complete(struct bcm2835_host * host)691 static void bcm2835_transfer_complete(struct bcm2835_host *host)
692 {
693 struct mmc_data *data;
694
695 WARN_ON(!host->data_complete);
696
697 data = host->data;
698 host->data = NULL;
699
700 /* Need to send CMD12 if -
701 * a) open-ended multiblock transfer (no CMD23)
702 * b) error in multiblock transfer
703 */
704 if (host->mrq->stop && (data->error || !host->use_sbc)) {
705 if (bcm2835_send_command(host, host->mrq->stop)) {
706 /* No busy, so poll for completion */
707 if (!host->use_busy)
708 bcm2835_finish_command(host);
709 }
710 } else {
711 bcm2835_wait_transfer_complete(host);
712 bcm2835_finish_request(host);
713 }
714 }
715
bcm2835_finish_data(struct bcm2835_host * host)716 static void bcm2835_finish_data(struct bcm2835_host *host)
717 {
718 struct device *dev = &host->pdev->dev;
719 struct mmc_data *data;
720
721 data = host->data;
722
723 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
724 writel(host->hcfg, host->ioaddr + SDHCFG);
725
726 data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks);
727
728 host->data_complete = true;
729
730 if (host->cmd) {
731 /* Data managed to finish before the
732 * command completed. Make sure we do
733 * things in the proper order.
734 */
735 dev_dbg(dev, "Finished early - HSTS %08x\n",
736 readl(host->ioaddr + SDHSTS));
737 } else {
738 bcm2835_transfer_complete(host);
739 }
740 }
741
bcm2835_finish_command(struct bcm2835_host * host)742 static void bcm2835_finish_command(struct bcm2835_host *host)
743 {
744 struct device *dev = &host->pdev->dev;
745 struct mmc_command *cmd = host->cmd;
746 u32 sdcmd;
747
748 sdcmd = bcm2835_read_wait_sdcmd(host, 100);
749
750 /* Check for errors */
751 if (sdcmd & SDCMD_NEW_FLAG) {
752 dev_err(dev, "command never completed.\n");
753 bcm2835_dumpregs(host);
754 host->cmd->error = -EIO;
755 bcm2835_finish_request(host);
756 return;
757 } else if (sdcmd & SDCMD_FAIL_FLAG) {
758 u32 sdhsts = readl(host->ioaddr + SDHSTS);
759
760 /* Clear the errors */
761 writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS);
762
763 if (!(sdhsts & SDHSTS_CRC7_ERROR) ||
764 (host->cmd->opcode != MMC_SEND_OP_COND)) {
765 u32 edm, fsm;
766
767 if (sdhsts & SDHSTS_CMD_TIME_OUT) {
768 host->cmd->error = -ETIMEDOUT;
769 } else {
770 dev_err(dev, "unexpected command %d error\n",
771 host->cmd->opcode);
772 bcm2835_dumpregs(host);
773 host->cmd->error = -EILSEQ;
774 }
775 edm = readl(host->ioaddr + SDEDM);
776 fsm = edm & SDEDM_FSM_MASK;
777 if (fsm == SDEDM_FSM_READWAIT ||
778 fsm == SDEDM_FSM_WRITESTART1)
779 /* Kick the FSM out of its wait */
780 writel(edm | SDEDM_FORCE_DATA_MODE,
781 host->ioaddr + SDEDM);
782 bcm2835_finish_request(host);
783 return;
784 }
785 }
786
787 if (cmd->flags & MMC_RSP_PRESENT) {
788 if (cmd->flags & MMC_RSP_136) {
789 int i;
790
791 for (i = 0; i < 4; i++) {
792 cmd->resp[3 - i] =
793 readl(host->ioaddr + SDRSP0 + i * 4);
794 }
795 } else {
796 cmd->resp[0] = readl(host->ioaddr + SDRSP0);
797 }
798 }
799
800 if (cmd == host->mrq->sbc) {
801 /* Finished CMD23, now send actual command. */
802 host->cmd = NULL;
803 if (bcm2835_send_command(host, host->mrq->cmd)) {
804 if (host->data && host->dma_desc)
805 /* DMA transfer starts now, PIO starts
806 * after irq
807 */
808 bcm2835_start_dma(host);
809
810 if (!host->use_busy)
811 bcm2835_finish_command(host);
812 }
813 } else if (cmd == host->mrq->stop) {
814 /* Finished CMD12 */
815 bcm2835_finish_request(host);
816 } else {
817 /* Processed actual command. */
818 host->cmd = NULL;
819 if (!host->data)
820 bcm2835_finish_request(host);
821 else if (host->data_complete)
822 bcm2835_transfer_complete(host);
823 }
824 }
825
bcm2835_timeout(struct work_struct * work)826 static void bcm2835_timeout(struct work_struct *work)
827 {
828 struct delayed_work *d = to_delayed_work(work);
829 struct bcm2835_host *host =
830 container_of(d, struct bcm2835_host, timeout_work);
831 struct device *dev = &host->pdev->dev;
832
833 mutex_lock(&host->mutex);
834
835 if (host->mrq) {
836 dev_err(dev, "timeout waiting for hardware interrupt.\n");
837 bcm2835_dumpregs(host);
838
839 bcm2835_reset(mmc_from_priv(host));
840
841 if (host->data) {
842 host->data->error = -ETIMEDOUT;
843 bcm2835_finish_data(host);
844 } else {
845 if (host->cmd)
846 host->cmd->error = -ETIMEDOUT;
847 else
848 host->mrq->cmd->error = -ETIMEDOUT;
849
850 bcm2835_finish_request(host);
851 }
852 }
853
854 mutex_unlock(&host->mutex);
855 }
856
bcm2835_check_cmd_error(struct bcm2835_host * host,u32 intmask)857 static bool bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)
858 {
859 struct device *dev = &host->pdev->dev;
860
861 if (!(intmask & SDHSTS_ERROR_MASK))
862 return false;
863
864 if (!host->cmd)
865 return true;
866
867 dev_err(dev, "sdhost_busy_irq: intmask %08x\n", intmask);
868 if (intmask & SDHSTS_CRC7_ERROR) {
869 host->cmd->error = -EILSEQ;
870 } else if (intmask & (SDHSTS_CRC16_ERROR |
871 SDHSTS_FIFO_ERROR)) {
872 if (host->mrq->data)
873 host->mrq->data->error = -EILSEQ;
874 else
875 host->cmd->error = -EILSEQ;
876 } else if (intmask & SDHSTS_REW_TIME_OUT) {
877 if (host->mrq->data)
878 host->mrq->data->error = -ETIMEDOUT;
879 else
880 host->cmd->error = -ETIMEDOUT;
881 } else if (intmask & SDHSTS_CMD_TIME_OUT) {
882 host->cmd->error = -ETIMEDOUT;
883 }
884 bcm2835_dumpregs(host);
885 return true;
886 }
887
bcm2835_check_data_error(struct bcm2835_host * host,u32 intmask)888 static void bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)
889 {
890 if (!host->data)
891 return;
892 if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))
893 host->data->error = -EILSEQ;
894 if (intmask & SDHSTS_REW_TIME_OUT)
895 host->data->error = -ETIMEDOUT;
896 }
897
bcm2835_busy_irq(struct bcm2835_host * host)898 static void bcm2835_busy_irq(struct bcm2835_host *host)
899 {
900 if (WARN_ON(!host->cmd)) {
901 bcm2835_dumpregs(host);
902 return;
903 }
904
905 if (WARN_ON(!host->use_busy)) {
906 bcm2835_dumpregs(host);
907 return;
908 }
909 host->use_busy = false;
910
911 bcm2835_finish_command(host);
912 }
913
bcm2835_data_irq(struct bcm2835_host * host,u32 intmask)914 static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask)
915 {
916 /* There are no dedicated data/space available interrupt
917 * status bits, so it is necessary to use the single shared
918 * data/space available FIFO status bits. It is therefore not
919 * an error to get here when there is no data transfer in
920 * progress.
921 */
922 if (!host->data)
923 return;
924
925 bcm2835_check_data_error(host, intmask);
926 if (host->data->error)
927 goto finished;
928
929 if (host->data->flags & MMC_DATA_WRITE) {
930 /* Use the block interrupt for writes after the first block */
931 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN);
932 host->hcfg |= SDHCFG_BLOCK_IRPT_EN;
933 writel(host->hcfg, host->ioaddr + SDHCFG);
934 bcm2835_transfer_pio(host);
935 } else {
936 bcm2835_transfer_pio(host);
937 host->blocks--;
938 if ((host->blocks == 0) || host->data->error)
939 goto finished;
940 }
941 return;
942
943 finished:
944 host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
945 writel(host->hcfg, host->ioaddr + SDHCFG);
946 }
947
bcm2835_data_threaded_irq(struct bcm2835_host * host)948 static void bcm2835_data_threaded_irq(struct bcm2835_host *host)
949 {
950 if (!host->data)
951 return;
952 if ((host->blocks == 0) || host->data->error)
953 bcm2835_finish_data(host);
954 }
955
bcm2835_block_irq(struct bcm2835_host * host)956 static void bcm2835_block_irq(struct bcm2835_host *host)
957 {
958 if (WARN_ON(!host->data)) {
959 bcm2835_dumpregs(host);
960 return;
961 }
962
963 if (!host->dma_desc) {
964 WARN_ON(!host->blocks);
965 if (host->data->error || (--host->blocks == 0))
966 bcm2835_finish_data(host);
967 else
968 bcm2835_transfer_pio(host);
969 } else if (host->data->flags & MMC_DATA_WRITE) {
970 bcm2835_finish_data(host);
971 }
972 }
973
bcm2835_irq(int irq,void * dev_id)974 static irqreturn_t bcm2835_irq(int irq, void *dev_id)
975 {
976 irqreturn_t result = IRQ_NONE;
977 struct bcm2835_host *host = dev_id;
978 u32 intmask;
979
980 spin_lock(&host->lock);
981
982 intmask = readl(host->ioaddr + SDHSTS);
983
984 writel(SDHSTS_BUSY_IRPT |
985 SDHSTS_BLOCK_IRPT |
986 SDHSTS_SDIO_IRPT |
987 SDHSTS_DATA_FLAG,
988 host->ioaddr + SDHSTS);
989
990 if (intmask & SDHSTS_BLOCK_IRPT) {
991 bcm2835_check_data_error(host, intmask);
992 host->irq_block = true;
993 result = IRQ_WAKE_THREAD;
994 }
995
996 if (intmask & SDHSTS_BUSY_IRPT) {
997 if (!bcm2835_check_cmd_error(host, intmask)) {
998 host->irq_busy = true;
999 result = IRQ_WAKE_THREAD;
1000 } else {
1001 result = IRQ_HANDLED;
1002 }
1003 }
1004
1005 /* There is no true data interrupt status bit, so it is
1006 * necessary to qualify the data flag with the interrupt
1007 * enable bit.
1008 */
1009 if ((intmask & SDHSTS_DATA_FLAG) &&
1010 (host->hcfg & SDHCFG_DATA_IRPT_EN)) {
1011 bcm2835_data_irq(host, intmask);
1012 host->irq_data = true;
1013 result = IRQ_WAKE_THREAD;
1014 }
1015
1016 spin_unlock(&host->lock);
1017
1018 return result;
1019 }
1020
bcm2835_threaded_irq(int irq,void * dev_id)1021 static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id)
1022 {
1023 struct bcm2835_host *host = dev_id;
1024 unsigned long flags;
1025 bool block, busy, data;
1026
1027 spin_lock_irqsave(&host->lock, flags);
1028
1029 block = host->irq_block;
1030 busy = host->irq_busy;
1031 data = host->irq_data;
1032 host->irq_block = false;
1033 host->irq_busy = false;
1034 host->irq_data = false;
1035
1036 spin_unlock_irqrestore(&host->lock, flags);
1037
1038 mutex_lock(&host->mutex);
1039
1040 if (block)
1041 bcm2835_block_irq(host);
1042 if (busy)
1043 bcm2835_busy_irq(host);
1044 if (data)
1045 bcm2835_data_threaded_irq(host);
1046
1047 mutex_unlock(&host->mutex);
1048
1049 return IRQ_HANDLED;
1050 }
1051
bcm2835_dma_complete_work(struct work_struct * work)1052 static void bcm2835_dma_complete_work(struct work_struct *work)
1053 {
1054 struct bcm2835_host *host =
1055 container_of(work, struct bcm2835_host, dma_work);
1056 struct mmc_data *data;
1057
1058 mutex_lock(&host->mutex);
1059
1060 data = host->data;
1061
1062 if (host->dma_chan) {
1063 dma_unmap_sg(host->dma_chan->device->dev,
1064 data->sg, data->sg_len,
1065 host->dma_dir);
1066
1067 host->dma_chan = NULL;
1068 }
1069
1070 if (host->drain_words) {
1071 unsigned long flags;
1072 void *page;
1073 u32 *buf;
1074
1075 if (host->drain_offset & PAGE_MASK) {
1076 host->drain_page += host->drain_offset >> PAGE_SHIFT;
1077 host->drain_offset &= ~PAGE_MASK;
1078 }
1079 local_irq_save(flags);
1080 page = kmap_atomic(host->drain_page);
1081 buf = page + host->drain_offset;
1082
1083 while (host->drain_words) {
1084 u32 edm = readl(host->ioaddr + SDEDM);
1085
1086 if ((edm >> 4) & 0x1f)
1087 *(buf++) = readl(host->ioaddr + SDDATA);
1088 host->drain_words--;
1089 }
1090
1091 kunmap_atomic(page);
1092 local_irq_restore(flags);
1093 }
1094
1095 bcm2835_finish_data(host);
1096
1097 mutex_unlock(&host->mutex);
1098 }
1099
bcm2835_set_clock(struct bcm2835_host * host,unsigned int clock)1100 static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)
1101 {
1102 struct mmc_host *mmc = mmc_from_priv(host);
1103 int div;
1104
1105 /* The SDCDIV register has 11 bits, and holds (div - 2). But
1106 * in data mode the max is 50MHz wihout a minimum, and only
1107 * the bottom 3 bits are used. Since the switch over is
1108 * automatic (unless we have marked the card as slow...),
1109 * chosen values have to make sense in both modes. Ident mode
1110 * must be 100-400KHz, so can range check the requested
1111 * clock. CMD15 must be used to return to data mode, so this
1112 * can be monitored.
1113 *
1114 * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz
1115 * 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz
1116 *
1117 * 623->400KHz/27.8MHz
1118 * reset value (507)->491159/50MHz
1119 *
1120 * BUT, the 3-bit clock divisor in data mode is too small if
1121 * the core clock is higher than 250MHz, so instead use the
1122 * SLOW_CARD configuration bit to force the use of the ident
1123 * clock divisor at all times.
1124 */
1125
1126 if (clock < 100000) {
1127 /* Can't stop the clock, but make it as slow as possible
1128 * to show willing
1129 */
1130 host->cdiv = SDCDIV_MAX_CDIV;
1131 writel(host->cdiv, host->ioaddr + SDCDIV);
1132 return;
1133 }
1134
1135 div = host->max_clk / clock;
1136 if (div < 2)
1137 div = 2;
1138 if ((host->max_clk / div) > clock)
1139 div++;
1140 div -= 2;
1141
1142 if (div > SDCDIV_MAX_CDIV)
1143 div = SDCDIV_MAX_CDIV;
1144
1145 clock = host->max_clk / (div + 2);
1146 mmc->actual_clock = clock;
1147
1148 /* Calibrate some delays */
1149
1150 host->ns_per_fifo_word = (1000000000 / clock) *
1151 ((mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32);
1152
1153 host->cdiv = div;
1154 writel(host->cdiv, host->ioaddr + SDCDIV);
1155
1156 /* Set the timeout to 500ms */
1157 writel(mmc->actual_clock / 2, host->ioaddr + SDTOUT);
1158 }
1159
bcm2835_request(struct mmc_host * mmc,struct mmc_request * mrq)1160 static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq)
1161 {
1162 struct bcm2835_host *host = mmc_priv(mmc);
1163 struct device *dev = &host->pdev->dev;
1164 u32 edm, fsm;
1165
1166 /* Reset the error statuses in case this is a retry */
1167 if (mrq->sbc)
1168 mrq->sbc->error = 0;
1169 if (mrq->cmd)
1170 mrq->cmd->error = 0;
1171 if (mrq->data)
1172 mrq->data->error = 0;
1173 if (mrq->stop)
1174 mrq->stop->error = 0;
1175
1176 if (mrq->data && !is_power_of_2(mrq->data->blksz)) {
1177 dev_err(dev, "unsupported block size (%d bytes)\n",
1178 mrq->data->blksz);
1179
1180 if (mrq->cmd)
1181 mrq->cmd->error = -EINVAL;
1182
1183 mmc_request_done(mmc, mrq);
1184 return;
1185 }
1186
1187 mutex_lock(&host->mutex);
1188
1189 WARN_ON(host->mrq);
1190 host->mrq = mrq;
1191
1192 edm = readl(host->ioaddr + SDEDM);
1193 fsm = edm & SDEDM_FSM_MASK;
1194
1195 if ((fsm != SDEDM_FSM_IDENTMODE) &&
1196 (fsm != SDEDM_FSM_DATAMODE)) {
1197 dev_err(dev, "previous command (%d) not complete (EDM %08x)\n",
1198 readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK,
1199 edm);
1200 bcm2835_dumpregs(host);
1201
1202 if (mrq->cmd)
1203 mrq->cmd->error = -EILSEQ;
1204
1205 bcm2835_finish_request(host);
1206 mutex_unlock(&host->mutex);
1207 return;
1208 }
1209
1210 if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD))
1211 bcm2835_prepare_dma(host, mrq->data);
1212
1213 host->use_sbc = !!mrq->sbc && host->mrq->data &&
1214 (host->mrq->data->flags & MMC_DATA_READ);
1215 if (host->use_sbc) {
1216 if (bcm2835_send_command(host, mrq->sbc)) {
1217 if (!host->use_busy)
1218 bcm2835_finish_command(host);
1219 }
1220 } else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) {
1221 if (host->data && host->dma_desc) {
1222 /* DMA transfer starts now, PIO starts after irq */
1223 bcm2835_start_dma(host);
1224 }
1225
1226 if (!host->use_busy)
1227 bcm2835_finish_command(host);
1228 }
1229
1230 mutex_unlock(&host->mutex);
1231 }
1232
bcm2835_set_ios(struct mmc_host * mmc,struct mmc_ios * ios)1233 static void bcm2835_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1234 {
1235 struct bcm2835_host *host = mmc_priv(mmc);
1236
1237 mutex_lock(&host->mutex);
1238
1239 if (!ios->clock || ios->clock != host->clock) {
1240 bcm2835_set_clock(host, ios->clock);
1241 host->clock = ios->clock;
1242 }
1243
1244 /* set bus width */
1245 host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;
1246 if (ios->bus_width == MMC_BUS_WIDTH_4)
1247 host->hcfg |= SDHCFG_WIDE_EXT_BUS;
1248
1249 host->hcfg |= SDHCFG_WIDE_INT_BUS;
1250
1251 /* Disable clever clock switching, to cope with fast core clocks */
1252 host->hcfg |= SDHCFG_SLOW_CARD;
1253
1254 writel(host->hcfg, host->ioaddr + SDHCFG);
1255
1256 mutex_unlock(&host->mutex);
1257 }
1258
1259 static const struct mmc_host_ops bcm2835_ops = {
1260 .request = bcm2835_request,
1261 .set_ios = bcm2835_set_ios,
1262 .hw_reset = bcm2835_reset,
1263 };
1264
bcm2835_add_host(struct bcm2835_host * host)1265 static int bcm2835_add_host(struct bcm2835_host *host)
1266 {
1267 struct mmc_host *mmc = mmc_from_priv(host);
1268 struct device *dev = &host->pdev->dev;
1269 char pio_limit_string[20];
1270 int ret;
1271
1272 if (!mmc->f_max || mmc->f_max > host->max_clk)
1273 mmc->f_max = host->max_clk;
1274 mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV;
1275
1276 mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000);
1277
1278 dev_dbg(dev, "f_max %d, f_min %d, max_busy_timeout %d\n",
1279 mmc->f_max, mmc->f_min, mmc->max_busy_timeout);
1280
1281 /* host controller capabilities */
1282 mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
1283 MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_CMD23;
1284
1285 spin_lock_init(&host->lock);
1286 mutex_init(&host->mutex);
1287
1288 if (!host->dma_chan_rxtx) {
1289 dev_warn(dev, "unable to initialise DMA channel. Falling back to PIO\n");
1290 host->use_dma = false;
1291 } else {
1292 host->use_dma = true;
1293
1294 host->dma_cfg_tx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1295 host->dma_cfg_tx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1296 host->dma_cfg_tx.slave_id = 13; /* DREQ channel */
1297 host->dma_cfg_tx.direction = DMA_MEM_TO_DEV;
1298 host->dma_cfg_tx.src_addr = 0;
1299 host->dma_cfg_tx.dst_addr = host->phys_addr + SDDATA;
1300
1301 host->dma_cfg_rx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1302 host->dma_cfg_rx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1303 host->dma_cfg_rx.slave_id = 13; /* DREQ channel */
1304 host->dma_cfg_rx.direction = DMA_DEV_TO_MEM;
1305 host->dma_cfg_rx.src_addr = host->phys_addr + SDDATA;
1306 host->dma_cfg_rx.dst_addr = 0;
1307
1308 if (dmaengine_slave_config(host->dma_chan_rxtx,
1309 &host->dma_cfg_tx) != 0 ||
1310 dmaengine_slave_config(host->dma_chan_rxtx,
1311 &host->dma_cfg_rx) != 0)
1312 host->use_dma = false;
1313 }
1314
1315 mmc->max_segs = 128;
1316 mmc->max_req_size = min_t(size_t, 524288, dma_max_mapping_size(dev));
1317 mmc->max_seg_size = mmc->max_req_size;
1318 mmc->max_blk_size = 1024;
1319 mmc->max_blk_count = 65535;
1320
1321 /* report supported voltage ranges */
1322 mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1323
1324 INIT_WORK(&host->dma_work, bcm2835_dma_complete_work);
1325 INIT_DELAYED_WORK(&host->timeout_work, bcm2835_timeout);
1326
1327 /* Set interrupt enables */
1328 host->hcfg = SDHCFG_BUSY_IRPT_EN;
1329
1330 bcm2835_reset_internal(host);
1331
1332 ret = request_threaded_irq(host->irq, bcm2835_irq,
1333 bcm2835_threaded_irq,
1334 0, mmc_hostname(mmc), host);
1335 if (ret) {
1336 dev_err(dev, "failed to request IRQ %d: %d\n", host->irq, ret);
1337 return ret;
1338 }
1339
1340 ret = mmc_add_host(mmc);
1341 if (ret) {
1342 free_irq(host->irq, host);
1343 return ret;
1344 }
1345
1346 pio_limit_string[0] = '\0';
1347 if (host->use_dma && (PIO_THRESHOLD > 0))
1348 sprintf(pio_limit_string, " (>%d)", PIO_THRESHOLD);
1349 dev_info(dev, "loaded - DMA %s%s\n",
1350 host->use_dma ? "enabled" : "disabled", pio_limit_string);
1351
1352 return 0;
1353 }
1354
bcm2835_probe(struct platform_device * pdev)1355 static int bcm2835_probe(struct platform_device *pdev)
1356 {
1357 struct device *dev = &pdev->dev;
1358 struct clk *clk;
1359 struct bcm2835_host *host;
1360 struct mmc_host *mmc;
1361 const __be32 *regaddr_p;
1362 int ret;
1363
1364 dev_dbg(dev, "%s\n", __func__);
1365 mmc = mmc_alloc_host(sizeof(*host), dev);
1366 if (!mmc)
1367 return -ENOMEM;
1368
1369 mmc->ops = &bcm2835_ops;
1370 host = mmc_priv(mmc);
1371 host->pdev = pdev;
1372 spin_lock_init(&host->lock);
1373
1374 host->ioaddr = devm_platform_ioremap_resource(pdev, 0);
1375 if (IS_ERR(host->ioaddr)) {
1376 ret = PTR_ERR(host->ioaddr);
1377 goto err;
1378 }
1379
1380 /* Parse OF address directly to get the physical address for
1381 * DMA to our registers.
1382 */
1383 regaddr_p = of_get_address(pdev->dev.of_node, 0, NULL, NULL);
1384 if (!regaddr_p) {
1385 dev_err(dev, "Can't get phys address\n");
1386 ret = -EINVAL;
1387 goto err;
1388 }
1389
1390 host->phys_addr = be32_to_cpup(regaddr_p);
1391
1392 host->dma_chan = NULL;
1393 host->dma_desc = NULL;
1394
1395 host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx");
1396 if (IS_ERR(host->dma_chan_rxtx)) {
1397 ret = PTR_ERR(host->dma_chan_rxtx);
1398 host->dma_chan_rxtx = NULL;
1399
1400 if (ret == -EPROBE_DEFER)
1401 goto err;
1402
1403 /* Ignore errors to fall back to PIO mode */
1404 }
1405
1406
1407 clk = devm_clk_get(dev, NULL);
1408 if (IS_ERR(clk)) {
1409 ret = dev_err_probe(dev, PTR_ERR(clk), "could not get clk\n");
1410 goto err;
1411 }
1412
1413 host->max_clk = clk_get_rate(clk);
1414
1415 host->irq = platform_get_irq(pdev, 0);
1416 if (host->irq <= 0) {
1417 ret = -EINVAL;
1418 goto err;
1419 }
1420
1421 ret = mmc_of_parse(mmc);
1422 if (ret)
1423 goto err;
1424
1425 ret = bcm2835_add_host(host);
1426 if (ret)
1427 goto err;
1428
1429 platform_set_drvdata(pdev, host);
1430
1431 dev_dbg(dev, "%s -> OK\n", __func__);
1432
1433 return 0;
1434
1435 err:
1436 dev_dbg(dev, "%s -> err %d\n", __func__, ret);
1437 if (host->dma_chan_rxtx)
1438 dma_release_channel(host->dma_chan_rxtx);
1439 mmc_free_host(mmc);
1440
1441 return ret;
1442 }
1443
bcm2835_remove(struct platform_device * pdev)1444 static int bcm2835_remove(struct platform_device *pdev)
1445 {
1446 struct bcm2835_host *host = platform_get_drvdata(pdev);
1447 struct mmc_host *mmc = mmc_from_priv(host);
1448
1449 mmc_remove_host(mmc);
1450
1451 writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);
1452
1453 free_irq(host->irq, host);
1454
1455 cancel_work_sync(&host->dma_work);
1456 cancel_delayed_work_sync(&host->timeout_work);
1457
1458 if (host->dma_chan_rxtx)
1459 dma_release_channel(host->dma_chan_rxtx);
1460
1461 mmc_free_host(mmc);
1462
1463 return 0;
1464 }
1465
1466 static const struct of_device_id bcm2835_match[] = {
1467 { .compatible = "brcm,bcm2835-sdhost" },
1468 { }
1469 };
1470 MODULE_DEVICE_TABLE(of, bcm2835_match);
1471
1472 static struct platform_driver bcm2835_driver = {
1473 .probe = bcm2835_probe,
1474 .remove = bcm2835_remove,
1475 .driver = {
1476 .name = "sdhost-bcm2835",
1477 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1478 .of_match_table = bcm2835_match,
1479 },
1480 };
1481 module_platform_driver(bcm2835_driver);
1482
1483 MODULE_ALIAS("platform:sdhost-bcm2835");
1484 MODULE_DESCRIPTION("BCM2835 SDHost driver");
1485 MODULE_LICENSE("GPL v2");
1486 MODULE_AUTHOR("Phil Elwell");
1487